First introduced in June 2007, the ISL G operates on 100% natural gas which can be carried on the vehicle in either compressed (CNG) or liquefied (LNG) form. The ISL G can also run on renewable natural gas (RNG).

For best reliability and durability, the recommended maximum GCVW for the ISL G in linehaul tractor applications is 66,000 lb (29,943 kg). Recommended gearing to optimize fuel economy is 1700 - 1800 rpm for linehaul applications, and 1750-1900 rpm for vocational applications.

An initial valve adjustment must be performed after 1,000 hours (15,000 miles/24,140 km) of operation, and is an important step in achieving longer engine life.

ISL G Truck < 66,000 lbs (29,937 kg) GCVW

Maintenance Item^

Distance

Hours

Months

Check CAC cooler, piping, and Air cleaner

7,500 mi (12,000 km)

250

3

Oil and Filter*

15,000 mi (24,000 km)

500

6

Fuel Filter

30,000 mi (48,000 km)

1,000

12

Coolant Filter

15,000 mi (24,000 km)

500

6

Spark Plugs

45,000 mi (72,000 km)

1,500

18

Cooling System Flush

60,000 mi (96,000 km)

2,000

24

Overhead Set Adjustment**

60,000 mi (96,000 km)

2,000

24

Ignition Coil Extension

300,000 mi (480,000 km)

10,000

5 yrs

Air Cleaner / Element

Follow manufacturer's published recommendations

^Based on a duty cycle of 30 mph / 48 kph average speed. Distance intervals will increase or decrease based on average speed. * Requires Natural Gas Engine Oil - click here for more information.**Initial overhead set adjustment at 1,000 hours.

ISL G Urban Transit Bus and Refuse Truck

Maintenance Item^

Distance

Hours

Months

Oil and Filter*

7,500 mi (12,000 km)

500

6

Fuel Filter

15,000 mi (24,000 km)

1,000

12

Coolant Filter

7,500 mi (12,000 km)

500

6

Spark Plugs^

22,500 mi (36,000 km)

1,500

18

Cooling System Flush

30,000 mi (48,000 km)

2,000

24

Overhead Set Adjustment**

30,000 mi (48,000 km)

2,000

24

Ignition Coil Extension

150,000 mi (240,000 km)

10,000

5 yrs

Air Cleaner / Element

Follow manufacturer's published recommendations

^Based on duty cycle of 15 mph / 25 kph average speed. Distance intervals will increase or decrease based on average speed. * Requires Natural Gas Engine Oil - click here for more information.**Initial overhead set adjustment at 1,000 hours.

Default interval is the hours stated. Interval is whichever comes first – hours, miles or time.

Refer to QuickServe® Online or Owners Manual for complete details on maintenance intervals.

Factory-Built, Dedicated Natural Gas Engine – Manufactured on the same assembly line as Cummins diesels, the ISL G shares many components and parts with Cummins L Series diesels, inheriting their renowned simplicity.

Electronic Control Module: Provides full monitoring and control of engine sensors, fuel system and ignition system, with full interface capability to Cummins INSITE and diagnostic service tools.

Fuel Capability - Natural gas can be stored on the vehicle in either compressed (CNG) or liquefied (LNG) form. The ISL G can also operate on renewable natural gas or biomethane that meets fuel-quality specifications.